#1  
Old 10-22-2021, 06:01 PM
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gto19 gto19 is offline
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Default Rear defroster blowing fuses

Hey guys

I have a 69 Grand Prix with a rear defroster and every time I turn it on it blows the 25 amp fuse . Anyone have any ideas why ?

Thanks

  #2  
Old 10-22-2021, 10:45 PM
Goatracer1 Goatracer1 is offline
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Unplug the defroster and turn the switch on. If it still blows the fuse it’s in the wiring if not the fan is bad. Turn fan by hand. If it doesn’t turn smoothly you can try lubing it. OR do you have a grid in the glass?

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Old 10-22-2021, 11:15 PM
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Grid in the glass . There’s a relay in the trunk

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Old 10-26-2021, 11:26 PM
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Does it blow the fuse all the time or just when turned on? If the latter is the case does the fuse blow instantly when you turn it on or does it happen after a passage of time.

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  #5  
Old 10-27-2021, 12:04 AM
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It works on high but when I put it on low I hear the relay in the trunk start to chatter and it blows the fuse . I’ve found a new relay so I think that’s gonna fix the problem.

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Old 10-27-2021, 08:31 AM
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That sounds like the problem, might just need to clean the contact point on the relay. They get carbonized and it creates too much resistance for the circuit blowing the fuse.

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My Break Away Squad
1969 Fbird (Base, 350 & Sprint Cvt’s - 400HO & TA Hardtops)
1969 LeMans (2dr & 4dr Hardtop and a Cvt)
1969 LeMans Safari 2 seat Wagon
1969 GTO (2 Cvt, 2 Hardtops & Judge Hardtop)
1969 Catalina (3 Cvt’s & a 2dr hardtop)
1969 Ventura 2 Seat Wagon
1969 Executive 4dr Sedan
1969 Bonnie Cvt
1969 Bonnie 3 Seat Wagon (2 of them)
1969 Bonnie Brougham (4dr Hardtop & Cvt)
1969 Grand Prix SJ (2 of them)
1969 2+2 2dr Hardtop (Canadian model)
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